Mask set for deposition and method of manufacturing display panel using the same

ABSTRACT

A deposition mask set includes a first mask, a second mask, and a third mask. Each of the first, second, and third masks includes a first edge substantially parallel to a first direction, a second edge substantially parallel to a second direction, and a plurality of openings. Each of the openings includes a first opening side that is substantially parallel to a third direction and a second opening side that is substantially parallel to a fourth direction, and each of the openings corresponds to one of a first, second, or third color area at one of pixel areas. The third and fourth directions are not parallel to the first and second directions, and the first, second, and third color areas are adjacent to each other in the third direction.

CROSS-REFERENCE TO RELATED APPLICATION

This patent application claims priority to and the benefit of KoreanPatent Application No. 10-2015-0045661, filed on Mar. 31, 2015, thecontents of which are hereby incorporated by reference in theirentirety.

BACKGROUND

1. Field

The present disclosure relates to a mask set for deposition and a methodof manufacturing a display panel using the mask set.

2. Description of the Related Art

In general, a flat panel display or a semiconductor device ismanufactured by depositing various materials on a substrate. Adeposition process is carried out using a deposition mask. The materialsdeposited on the substrate form a thin film layer pattern.

In recent years, a density of the thin film pattern has become highaccording to a high-density integration of the semiconductor device anda high-resolution of the flat panel display.

An organic light emitting display device is widely used as the flatpanel display. The organic light emitting display device includes anorganic light emitting device including an anode, an organic lightemitting layer, and a cathode. In this case, holes and electronsinjected into the organic light emitting layer are recombined in theorganic light emitting layer to generate excitons, and the organic lightemitting display device emits light by the excitons that return to aground state from an excited state. The organic light emitting displaydevice displays an image using the light emission of the organic lightemitting layer.

The organic light emitting display device has a self-emissivecharacteristic and does not need a separate light source, and thus athickness and a weight of the organic light emitting display device maybe relatively reduced. In addition, because the organic light emittingdisplay device has various features, such as low power consumption, highbrightness, fast response time, etc., the organic light emitting displaydevice is considered as a next generation display device.

SUMMARY

The present disclosure provides a mask set for deposition, which mayhave improved strength.

The present disclosure provides a method of manufacturing a displaypanel using the mask set.

One or more embodiments of the inventive concept provide a depositionmask set including a first mask. The first mask includes a first edgesubstantially parallel to a first direction, a second edge substantiallyparallel to a second direction, and a plurality of first openings, eachof the first openings including a first opening side that issubstantially parallel to a third direction and a second opening sidethat is substantially parallel to a fourth direction, and each of thefirst openings corresponding to a first color area at one of pixelareas, wherein the pixel areas are in a matrix form along the first andsecond directions, wherein each of the pixel areas comprises a firstarea side that is substantially parallel to the third direction and asecond area side that is substantially parallel to the fourth direction,and wherein the third and fourth directions are not parallel to thefirst and second directions.

In one or more embodiments, the first mask may include a first section,a number of first sub-openings in the first section from among the firstopenings being less than a number of second sub-openings in the firstsection from among the first openings, wherein the first and secondsub-openings are overlapped with first and second pixel definitionlines, respectively, the first and second pixel definition lines beingsubstantially parallel to the third direction and overlapping with thefirst section, and wherein the second pixel definition line is adjacentto the first pixel definition line in the fourth direction.

In one or more embodiments, the deposition mask may further include asecond section adjacent to the first section in the fourth direction. Anumber of third sub-openings in the second section from among the firstopenings being equal to a number of fourth sub-openings in the secondsection from among the first openings, wherein the third and fourthsub-openings are overlapped with third and fourth pixel definitionlines, respectively, the third and fourth pixel definition lines beingsubstantially parallel to the third direction and overlapping with thesecond section, and wherein the fourth pixel definition line is adjacentto the third pixel definition line in the fourth direction.

In one or more embodiments, the deposition mask set may further includea third section adjacent to the second section in the fourth direction.A number of fifth sub-openings in the third section from among the firstopenings being greater than a number of sixth sub-openings in the thirdsection from among the first openings, wherein the fifth and sixthsub-openings are overlapped with fifth and sixth pixel definition lines,respectively, the fifth and sixth pixel definition lines beingsubstantially parallel to the third direction and overlapping with thethird section, and wherein the sixth pixel definition line is adjacentto the fifth pixel definition line in the fourth direction.

In one or more embodiments, the first and second directions may besubstantially perpendicular to each other and the third and fourthdirections may be substantially perpendicular to each other.

In one or more embodiments, the first and third directions form an angleof about 45 degrees.

In one or more embodiments, the deposition mask set may further includea second mask. The second mask includes a third edge substantiallyparallel to the first direction, a fourth edge substantially parallel tothe second direction, and a plurality of second openings, each of thesecond openings including a third opening side that is substantiallyparallel to the third direction and a fourth opening side that issubstantially parallel to the fourth direction, each of the secondopenings corresponding to a second color area and each second color areaat one of the pixel areas, and wherein the second color area is adjacentto the first color area in the third direction.

In one or more embodiments, the deposition mask set may further includea third mask. The third mask includes a fifth edge substantiallyparallel to the first direction, a sixth edge substantially parallel tothe second direction, and a plurality of third openings, each of thethird openings including a fifth opening side that is substantiallyparallel to the third direction and a sixth opening side that issubstantially parallel to the fourth direction, each of the thirdopenings corresponding to a third color area at one of the pixel areas,and wherein the third color area is adjacent to the second color area inthe third direction.

In one or more embodiments, the first, second, and third color areas ofeach of the pixel areas may not overlap with each other.

In one or more embodiments, centers of the first, second, and thirdcolor areas of each of the pixel areas may be aligned in the thirddirection.

In one or more embodiments, a length of the first opening side may bedifferent from a length of at least one of the third and fifth openingsides.

In one or more embodiments, a length of the second, fourth, and sixthopening sides may be the same.

One or more embodiments of the inventive concept provide a method ofmanufacturing a display panel, the method including: preparing asubstrate including a display part including first and second displaysides that are substantially parallel to first and second directions,respectively; defining a plurality of pixel areas on the substrate, thepixel areas being arranged in a matrix form along the first and seconddirections, each of the pixel areas including first and second areasides that are substantially parallel to third and fourth directions,respectively, the third and fourth directions being not parallel to thefirst and second directions; and depositing a first color material onthe substrate using a first mask to form a first color layer in a firstcolor area of each of the pixel areas, wherein the first mask includes afirst opening corresponding to the first color area of each of the pixelareas and includes first and second opening sides substantially parallelto the third and fourth directions, respectively.

In one or more embodiments, the method may further include depositing asecond color material on the substrate using a second mask to form asecond color layer in a second color area of each of the pixel areas,wherein the second mask includes a second opening corresponding to thesecond color area and includes third and fourth opening sidessubstantially parallel to the third and fourth directions, respectively,and the second color area is adjacent to the first color area in thethird direction.

In one or more embodiments, the method may further include depositing athird color material on the substrate using a third mask to form a thirdcolor layer in a third color area of each of the pixel areas, whereinthe third mask includes a third opening corresponding to the third colorarea and includes fifth and sixth opening sides substantially parallelto the third and fourth directions, respectively, and the third colorarea is adjacent to the second color area in the third direction.

In one or more embodiments, the substrate may include a first area, anumber of first pixel areas in the first area from among the pixel areasbeing less than a number of second pixel areas in the first area fromamong the pixel areas, wherein the first and second pixel areas areoverlapped with first and second pixel definition lines, respectively,the first and second pixel definition lines being substantially parallelto the third direction and overlapped with the first area, and whereinthe second pixel definition line is adjacent to the first pixeldefinition line in the fourth direction.

In one or more embodiments, the substrate may include a second areaadjacent to the first area in the fourth direction, a number of thirdpixel areas in the second area from among the pixel areas being equal toa number of fourth pixel areas in the second area from among the pixelareas, wherein the third and fourth pixel areas are overlapped withthird and fourth pixel definition lines, respectively, the third andfourth pixel definition lines being substantially parallel to the thirddirection and overlapped with the second area, and wherein the fourthpixel definition line is adjacent to the third pixel definition line inthe fourth direction.

In one or more embodiments, the substrate may include a third areaadjacent to the second area in the fourth direction, a number of fifthpixel areas in the third area from among the pixel areas being greaterthan a number of sixth pixel areas in the third area from among thepixel areas, wherein the fifth and sixth pixel areas are overlapped withfifth and sixth pixel definition lines, respectively, the fifth andsixth pixel definition lines being substantially parallel to the thirddirection and overlapped with the third area, and wherein the sixthpixel definition line is adjacent to the fifth pixel definition line inthe fourth direction.

According to the above, the strength of the masks may be improved by theshapes and arrangements of the openings of the masks. As such, thedensity of the openings of the masks may be improved. Thus, the displaypanel manufactured using the masks may have high resolution.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects of the present disclosure will becomereadily apparent by reference to the following detailed description whenconsidered in conjunction with the accompanying drawings wherein:

FIG. 1 is a plan view of a display panel according to one or moreexemplary embodiments of the present disclosure;

FIG. 2 is a plan view of a pixel of FIG. 1;

FIG. 3 is an exploded perspective view of a red sub-pixel of FIG. 2;

FIG. 4 is a plan view of a pixel area according to one or more exemplaryembodiments of the present disclosure;

FIG. 5 is a plan view of a mask set according to one or more exemplaryembodiments of the present disclosure;

FIG. 6 is a flowchart of a method of manufacturing a display panel usingthe mask set of FIG. 5;

FIG. 7 is a plan view of a lower substrate according to themanufacturing method of FIG. 6;

FIG. 8 is a plan view of the lower substrate and a first mask fordepositing a first color material according to the manufacturing methodof FIG. 6;

FIG. 9 is a plan view of the lower substrate and a second mask fordepositing a second color material according to the manufacturing methodof FIG. 6;

FIG. 10 is a plan view of the lower substrate and a third mask fordepositing a third color material according to the manufacturing methodof FIG. 6; and

FIG. 11 is a plan view of a display panel manufactured by themanufacturing method of FIG. 6.

DETAILED DESCRIPTION

Hereinafter, example embodiments are described in more detail withreference to the accompanying drawings, in which like reference numbersrefer to like elements throughout. The present invention, however, maybe embodied in various different forms, and should not be construed asbeing limited to only the illustrated embodiments herein. Rather, theseembodiments are provided as examples so that this disclosure will bethorough and complete, and will fully convey the aspects and features ofthe present invention to those skilled in the art. Accordingly,processes, elements, and techniques that are not necessary to thosehaving ordinary skill in the art for a complete understanding of theaspects and features of the present invention may not be described.Unless otherwise noted, like reference numerals denote like elementsthroughout the attached drawings and the written description, and thus,descriptions thereof will not be repeated. In the drawings, the relativesizes of elements, layers, and regions may be exaggerated for clarity.

It will be understood that, although the terms “first,” “second,”“third,” etc., may be used herein to describe various elements,components, regions, layers and/or sections, these elements, components,regions, layers and/or sections should not be limited by these terms.These terms are used to distinguish one element, component, region,layer or section from another element, component, region, layer orsection. Thus, a first element, component, region, layer or sectiondescribed below could be termed a second element, component, region,layer or section, without departing from the spirit and scope of thepresent invention.

It will be understood that when an element or layer is referred to asbeing “on,” “connected to,” or “coupled to” another element or layer, itcan be directly on, connected to, or coupled to the other element orlayer, or one or more intervening elements or layers may be present. Inaddition, it will also be understood that when an element or layer isreferred to as being “between” two elements or layers, it can be theonly element or layer between the two elements or layers, or one or moreintervening elements or layers may also be present.

The terminology used herein is for the purpose of describing particularembodiments and is not intended to be limiting of the present invention.As used herein, the singular forms “a” and “an” are intended to includethe plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises,”“comprising,” “includes,” and “including,” when used in thisspecification, specify the presence of the stated features, integers,steps, operations, elements, and/or components, but do not preclude thepresence or addition of one or more other features, integers, steps,operations, elements, components, and/or groups thereof. As used herein,the term “and/or” includes any and all combinations of one or more ofthe associated listed items. Expressions such as “at least one of,” whenpreceding a list of elements, modify the entire list of elements and donot modify the individual elements of the list.

As used herein, the term “substantially,” “about,” and similar terms areused as terms of approximation and not as terms of degree, and areintended to account for the inherent deviations in measured orcalculated values that would be recognized by those of ordinary skill inthe art. Further, the use of “may” when describing embodiments of thepresent invention refers to “one or more embodiments of the presentinvention.” As used herein, the terms “use,” “using,” and “used” may beconsidered synonymous with the terms “utilize,” “utilizing,” and“utilized,” respectively. Also, the term “exemplary” is intended torefer to an example or illustration.

The electronic or electric devices and/or any other relevant devices orcomponents according to embodiments of the present invention describedherein may be implemented utilizing any suitable hardware, firmware(e.g. an application-specific integrated circuit), software, or acombination of software, firmware, and hardware. For example, thevarious components of these devices may be formed on one integratedcircuit (IC) chip or on separate IC chips. Further, the variouscomponents of these devices may be implemented on a flexible printedcircuit film, a tape carrier package (TCP), a printed circuit board(PCB), or formed on one substrate. Further, the various components ofthese devices may be may be a process or thread, running on one or moreprocessors, in one or more computing devices, executing computer programinstructions and interacting with other system components for performingthe various functionalities described herein. The computer programinstructions are stored in a memory which may be implemented in acomputing device using a standard memory device, such as, for example, arandom access memory (RAM). The computer program instructions may alsobe stored in other non-transitory computer readable media such as, forexample, a CD-ROM, flash drive, or the like. Also, a person of skill inthe art should recognize that the functionality of various computingdevices may be combined or integrated into a single computing device, orthe functionality of a particular computing device may be distributedacross one or more other computing devices without departing from thespirit and scope of the exemplary embodiments of the present invention.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which the present invention belongs. Itwill be further understood that terms, such as those defined in commonlyused dictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art and/orthe present specification, and should not be interpreted in an idealizedor overly formal sense, unless expressly so defined herein.

Hereinafter, the present invention is explained with reference to theaccompanying drawings.

FIG. 1 is a plan view of a display panel 1000 according to one or moreexemplary embodiments of the present disclosure and FIG. 2 is a planview of a pixel shown in FIG. 1.

Referring to FIG. 1, in one or more embodiments, the display panel 1000includes a lower substrate 100, an upper substrate 900 facing the lowersubstrate 100, and a plurality of pixels PX disposed between the lowersubstrate 100 and the upper substrate 900.

The lower substrate 100 includes a display area (or display part) DA fordisplaying an image (e.g., a display area DA that is configured todisplay an image) and a non-display area (or non-display part) NA notdisplaying the image (e.g., a non-display area NA that is not configuredto display an image). The display area DA includes a plurality of pixelareas PA defined therein. The non-display area NA may be adjacent to atleast one side of the display area DA. For example, the non-display areaNA may be disposed to surround the display area DA. The non-display areaNA includes lines or drivers, which are arranged in the non-display areaNA to drive the pixels PX.

The lower substrate 100 may be a flexible substrate, but the presentdisclosure is not limited thereto. The lower substrate 100 may include apolymer with superior heat resistance and superior durability, such aspolyethylene terephthalate, polyethylene naphthalate, polycarbonate,polyarylate, polyether imide, polyether sulfone, polyimide, polymethylmethacrylate, etc., and/or a combination thereof, but the presentdisclosure is not limited thereto or thereby. The lower substrate 100may include various materials, e.g., metal or glass.

The pixels PX are disposed to respectively correspond to the pixel areasPA. Each pixel PX serves as a basic element for displaying a unit image(e.g., a basic element configured to display a unit image). The displaypanel 1000 has a resolution determined by the number of pixels PXarranged on the lower substrate 100. The pixels PX are arranged in amatrix form along a first direction DR1 and a second direction DR2 thatis substantially perpendicular to the first direction DR1. Forconvenience of explanation, FIG. 1 illustrates three pixels PX adjacentto each other and additional pixels PX are omitted.

Each of the pixels PX may include a plurality of sub-pixels SPX. Forexample, each of the pixels PX may include three sub-pixels SPX, but thepresent disclosure is not limited thereto or thereby. For example, eachof the pixels PX may include two or four or more sub-pixels SPX.

Each sub-pixel SPX may be configured to display a color (e.g., a primarycolor). Each sub-pixel SPX may be configured to display one of red,green, blue, and white colors, but the present disclosure is not limitedthereto or thereby. For example, the sub-pixels SPX may be configured todisplay one of yellow, cyan, and magenta colors.

Referring to FIG. 2, the pixel area PA includes a first side (e.g., afirst area side AS1) that is substantially parallel to a third directionDR3, which is different from the first and second directions DR1 and DR2(e.g., which intersects or is not parallel to the first and seconddirections DR1 and DR2), and a second side (e.g., a second area sideAS2) that is substantially parallel to a fourth direction DR4, which isdifferent from the first and second directions DR1 and DR2 (e.g., whichintersects or is not parallel to the first and second directions DR1 andDR2). For example, the pixel area PA may have a substantiallyrectangular shape. As such, an included angle between the first andthird directions DR1 and DR3 may be about 45 degrees and the third andfourth directions DR3 and DR4 may be substantially perpendicular to eachother. The first and second area sides AS1 and AS2 may be long and shortsides of the pixel area PA, respectively. The first area side AS1 mayhave a length that is two times greater than a length of the second areaside AS2.

The pixel area PA may include a plurality of color areas. For example,the color areas may include a red area RA, a green area GA, and a bluearea BA.

The red, green, and blue areas RA, GA, and BA are arranged along thethird direction DR3 and spaced apart from each other (e.g., spaced apartfrom each other by a predetermined distance). For example, a red areacenter RC of the red area RA, a green area center of the green area GA,and a blue area center BC of the blue area BA each overlap with a centerline CL that is substantially parallel to the third direction DR3. Thered, green, and blue areas RA, GA, and BA are not overlapped with eachother.

The pixel PX includes red, green, and blue sub-pixels RPX, GPX, and BPX,which are respectively for displaying red, green, and blue images. Thered, green, and blue sub-pixels RPX, GPX, and BPX are disposed torespectively correspond to the red, green, and blue areas RA, GA, andBA. In other words, the red, green, and blue sub-pixels RPX, GPX, andBPX are disposed such that the centers of the red, green, and bluesub-pixels RPX, GPX, and BPX are on the center line CL.

Each of the red, green, and blue sub-pixels RPX, GPX, and BPX includes afirst pixel side PS1 and a second pixel side PS2, which aresubstantially parallel to the third and fourth directions DR3 and DR4,respectively. The first and second pixel sides PS1 and PS2 mayrespectively be a short side and a long side of the red, green, and bluesub-pixels RPX, GPX, and BPX. As illustrated in FIG. 2, each of the red,green, and blue sub-pixels RPX, GPX, and BPX may have a substantiallyquadrangular shape, but the present disclosure is not limited thereto orthereby. For example, each of the red, green, and blue sub-pixels RPX,GPX, and BPX may have any suitable shape, such as a polygonal shape, acircular shape, an oval shape, etc.

As an example, in one or more embodiments, the second pixel sides PS2 ofthe red, green, and blue sub-pixels RPX, GPX, and BPX may have the samelength and the first pixel sides PS1 of the red, green, and bluesub-pixels RPX, GPX, and BPX may have different lengths. Because thered, green, and blue sub-pixels RPX, GPX, and BPX have a similarstructure, hereinafter, the red sub-pixel RPX is described as arepresentative example.

FIG. 3 is an exploded perspective view of the red sub-pixel RPX shown inFIG. 2.

Referring to FIG. 3, in one or more embodiments, the red sub-pixel RPXmay include an organic light emitting device LD and a device drivingcircuit DDC. The organic light emitting device LD and the device drivingcircuit DDC are disposed between the lower substrate 100 and the uppersubstrate 900 to correspond to the red area RA.

The red sub-pixel RPX may include a barrier layer to prevent orsubstantially prevent a foreign substance, e.g., moisture, oxygen, etc.,from infiltrating the organic light emitting device LD. The barrierlayer encapsulates the organic light emitting device LD to prevent orsubstantially prevent the organic light emitting device LD from beingexposed to the outside.

For example, the barrier layer may be an encapsulation member thatattaches the lower substrate 100, the upper substrate 900, and the lowerand upper substrates 100 and 900 or may be a thin film encapsulationlayer that covers the organic light emitting device LD. The thin filmencapsulation layer may have a single-layer structure of an organic orinorganic layer or a multi-layer structure of organic and inorganiclayers.

The lower substrate 100 may include a plurality of gate lines and aplurality of data lines. FIG. 3 illustrates first and second gate linesG1 and G2 among the gate lines and first and second data lines D1 and D2among the data lines. The gate lines G1 and G2 are insulated from thedata lines D1 and D2 while crossing the data lines D1 and D2. The gatelines G1 and G2 extend in the first direction DR1 and the data lines D1and D2 extend in the second direction DR2, but the present disclosure isnot limited thereto or thereby. For example, portions of the gate linesG1 and G2 and the data lines D1 and D2 may have a bent shape as long asthe gate lines G1 and G2 are insulated from and cross the data lines D1and D2. An area surrounded by the gate lines G1 and G2 and the datalines D1 and D2 may correspond to the red area RA.

In one or more embodiments, the device driving circuit DDC includes aswitching transistor Qs, a driving transistor Qd, and a storagecapacitor Cst.

The switching transistor Qs may include a control terminal N1, an inputterminal N2, and an output terminal N3. The control terminal N1 isconnected to the first gate line G1, the input terminal N2 is connectedto the first data line D1, and the output terminal N3 is connected tothe driving transistor Qd. The switching transistor Qs applies a datavoltage, which is applied to the first data line D1, to the drivingtransistor Qd in response to a gate signal applied to the first gateline G1.

The driving transistor Qd may include a control terminal N4, an inputterminal N5, and an output terminal N6. The control terminal N4 isconnected to the output terminal N3 of the switching transistor Qs, theinput terminal N5 receives a driving voltage ELVdd (e.g., is configuredto receive a driving voltage ELVdd), and the output terminal N6 isconnected to the organic light emitting device LD. The drivingtransistor Qd applies an output current Id, which has a level thatvaries depending on a voltage between the control terminal N4 and theoutput terminal N6, to the organic light emitting device LD.

The storage capacitor Cst is connected between the output terminal N3 ofthe switching capacitor Qs and the input terminal N5 of the drivingtransistor Qd. The storage capacitor Cst is charged with a voltageapplied to the control terminal N4 of the driving transistor Qd andmaintains the voltage charged therein during a predetermined time periodafter the switching transistor Qs is turned off.

The lower substrate 100 may further include a driving voltage line. Thedriving voltage line may extend substantially parallel to the first gateline G1 or extends substantially parallel to the first data line D1. Thedriving voltage line receives the driving voltage ELVdd and is connectedto the input terminal N5 of the driving transistor Qd.

In one or more embodiments, the organic light emitting device LD mayinclude a first electrode AE, an organic layer OL, and a secondelectrode CE.

In one or more embodiments, the first electrode AE is an anode electrodeand the second electrode CE is a cathode electrode. The first electrodeAE is connected to the output terminal N6 of the driving transistor Qdand provides the organic layer OL with holes. The second electrode CEreceives a common voltage ELVss and provides the organic layer OL withelectrons. The organic layer OL is disposed between the first electrodeAE and the second electrode CE. The organic layer OL may include aplurality of layers and an organic material.

The holes are injected into the organic layer OL from the firstelectrode AE and the electrons are injected into the organic layer OL.Holes and electrons injected into the organic layer OL are recombined inthe organic layer OL to generate excitons, and the organic layer OLemits the light by the excitons that return to a ground state from anexcited state. The light emitted from the organic layer OL has anintensity determined by the output current Id flowing through the outputterminal N6 of the driving transistor Qd.

As illustrated in FIG. 3, in some embodiments, the second electrode CEmay be disposed on the first electrode AE, but the present disclosure isnot limited thereto or thereby. For example, in some embodiments, thefirst electrode AE may be disposed on the second electrode CE.

An inner space 320 defined by the lower substrate 100 and the uppersubstrate 900 may be maintained in a vacuum state, but the presentdisclosure is not limited thereto or thereby. For example, the innerspace 320 may be filled with an inert gas such as a nitrogen gas (N₂) orwith a filling member including an insulating material.

The organic light emitting device LD may include an optical compensationlayer. The optical compensation layer scatters the light emitted fromthe organic layer OL such that the light emitted from the organic layerOL has a wide output angle or improves a light extraction efficiency ofthe organic light emitting device LD.

FIG. 4 is a plan view of a pixel area according to one or more exemplaryembodiments of the present disclosure.

Referring to FIG. 4, in one or more embodiments, the pixel areas PA aredefined on the lower substrate 100 with respect to first and seconddisplay sides DS1 and DS2 of the display area DA. The first and seconddisplay sides DS1 and DS2 are substantially parallel to the first andsecond directions DR1 and DR2, respectively.

The pixel areas PA are arranged in a matrix form along first to thirdrows R1 to R3 and first to fourth columns C1 to C4. Hereinafter, forconvenience of explanation, a pixel area disposed at an m-th row and ann-th column among the pixel areas PA is referred to as an “m-th row andn-th column pixel area PAm_n”. For example, among the pixel areas PA, apixel area disposed at a second row and a second column is referred toas a “second-row and second-column pixel area PA2_2”.

The pixel areas PA are divided into six areas: a first pixel area PA1, asecond pixel area PA2, a third pixel area PA3, a fourth pixel area PA4,a fifth pixel area PA5 and a sixth pixel area PA6. The first to sixthpixel areas PA1 to PA6 are overlapped with first to sixth pixeldefinition lines PDL1 to PDL6, respectively.

The first to sixth pixel definition lines PDL1 to PDL6 are defined onthe display area DA and are substantially parallel to the thirddirection DR3. In addition, the first to sixth pixel definition linesPDL1 to PDL6 are sequentially arranged in the fourth direction DR4 andspaced apart (e.g., spaced apart from each other by a predetermineddistance). For example, a first-row and first-column pixel area PA1_1 isincluded in the first pixel area PA1, and a first-row and second-columnpixel area PA1_2 and a second-row and first-column pixel area PA2_1 areincluded in the second pixel area PA2.

The first to sixth pixel definition lines PDL1 to PDL6 are defined withrespect to the first and second display sides DS1 and DS2. In moredetail, the first pixel definition line PDL1 is spaced apart from afirst corner CN1 defined by the first and second display sides DS1 andDS2 by a first reference distance R1.

Similarly, the first to sixth pixel areas PA1 to PA6 are defined withrespect to the first and second display sides DS1 and DS2. In moredetail, the first-row and first-column pixel area PA1_1 is spaced apartfrom the first corner CN1 by a second reference distance R2.

First, second, and third areas A1, A2, and A3 are defined on the lowersubstrate 100. The first to third areas A1 to A3 are sequentiallydefined in the fourth direction D4 on the lower substrate 100. A firstboundary line B1 is defined between the first and second areas A1 and A2and a second boundary line B2 is defined between the second and thirdareas A2 and A3. The first and second boundary lines B1 and B2 aresubstantially parallel to the third direction DR3.

The first and second pixel areas PA1 and PA2 are included in the firstarea A1, the third and fourth pixel areas PA3 and PA4 are included inthe second area A2, and the fifth and sixth pixel areas PA5 and PA6 areincluded in the third area A3.

As an example, in one or more embodiments, a number of the first pixelareas PA1 is one and a number of the second pixel areas PA2 is two. Thatis, the number of the first pixel areas PA1 included in the first areaA1 is less than the number of the second pixel areas PA2 included in thefirst area A1.

In addition, a number of the third pixel areas PA3 is three and a numberof the fourth pixel areas PA2 is three. That is, the number of the thirdpixel areas PA3 included in the second area A2 is equal to the number ofthe fourth pixel areas PA2 included in the second area A2.

Further, a number of the fifth pixel areas PA5 is two and a number ofthe sixth pixel areas PA6 is one. That is, the number of the fifth pixelareas PA5 included in the third area A3 is greater than the number ofthe sixth pixel areas PA6 included in the third area A3.

FIG. 5 is a plan view of a mask set 400 according to one or moreexemplary embodiments of the present disclosure.

Referring to FIG. 5, the mask set 400 includes first, second, and thirdmasks MS1, MS2, and M3.

The first mask MS1 includes a first edge ED1, a second edge ED2, and aplurality of first openings OP1.

The first and second edges ED1 and ED2 are substantially parallel to thefirst and second directions DR1 and DR2, respectively.

Pixel areas PA (e.g., pixel areas PA that correspond to the pixel areasPA of the display panel 1000) are defined on the first mask MS1. Thepixel areas PA are defined by the first and second edges ED1 and ED2. Inmore detail, the first-row and first-column pixel area PA1_1 is spacedapart from a second corner CN2 formed by the first and second edges ED1and ED2 by a third reference distance R3. The third reference distanceR3 may be greater than the second reference distance R2 (refer to FIG.4).

The first openings OP1 are formed to respectively correspond to the redareas RA of the pixel areas PA of the display panel 1000. The firstopenings OP1 include first and second opening sides OS1 and OS2 that aresubstantially parallel to the third and fourth directions DR3 and DR4,respectively. The first openings OP1 may have a quadrangular shapecorresponding to the red area RA. The first and second opening sides OS1and OS2 may be a short side and a long side of the first openings OP1,respectively.

In more detail, the first openings OP1 are arranged in a matrix formalong the first and second directions DR1 and DR2. Hereinafter, forconvenience of explanation, a first opening disposed at an m-th row andan n-th column among the first openings OP1 is referred to as an “m-throw and n-th column first opening OPm_n”. For example, among the firstopenings OP1, a first opening disposed at a second row and a firstcolumn is referred to as a “second-row and first-column first openingOP2_1”.

The first openings OP1 are divided into six sub-openings: a firstsub-opening SOP1, a second sub-opening SOP2, a third sub-opening SOP3, afourth sub-opening SOP4, a fourth sub-opening SOP4, a fifth sub-openingSOP5, and a sixth sub-opening SOP6. Among the first openings OP1, thefirst to sixth sub-openings SOP1 to SOP6 are overlapped with the firstto sixth pixel definition lines PDL1 to PDL6, respectively. For example,the first sub-opening SOP1 includes a first-row and first-column firstopening OP1_1 and the second sub-opening SOP2 includes a first-row andsecond-column first opening OP1_2 and the second-row and first-row firstopening OP2_1.

The first to sixth pixel definition lines PDL1 to PDL6 are defined onthe first mask MS1 by the first and second edges ED1 and ED2. In moredetail, the first pixel definition line PDL1 is spaced apart from thesecond corner CN2 formed by the first and second edges ED1 and ED2 by afourth reference distance R4.

The first mask MS1 includes first, second, and third sections SC1, SC2,and SC3. The first to third sections SC1 to SC3 respectively correspondto the first to third areas A1 to A3.

In more detail, the first to third sections SC1 to SC3 are sequentiallyarranged in the fourth direction DR4 on the lower substrate 100. A firstsection boundary line is defined between the first and second sectionsSC1 and SC2 and a second section boundary line is defined between thesecond and third sections SC2 and SC3. The first and second sectionboundary lines are substantially parallel to the third direction DR3.

The first and second sub-openings SOP1 and SOP2 are formed in the firstsection SC1, the third and fourth sub-openings SOP3 and SOP4 are formedin the second section SC2, and the fifth and sixth sub-openings SOP5 andSOP6 are formed in the third section SC3.

As an example, a number of the first sub-openings SOP1 may be one and anumber of the second sub-openings SOP2 may be two. That is, the numberof the first sub-openings SOP1 included in the first section SC1 is lessthan the number of the second sub-openings SOP2 included in the firstsection SC1.

In addition, a number of the third sub-openings SOP3 may be three and anumber of the fourth sub-openings SOP4 may be three. That is, the numberof the third sub-openings SOP3 included in the second section SC2 isequal to the number of the fourth sub-openings SOP4 included in thesecond section SC2.

Further, a number of the fifth sub-openings SOP5 may be two and a numberof the sixth sub-openings SOP6 may be one. That is, the number of thefifth sub-openings SOP5 included in the third section SC3 is greaterthan the number of the sixth sub-openings SOP6 included in the thirdsection SC3.

As described above, when the first openings OP1 are formed on the firstmask MS1, strength of the first mask MS1 may be improved. Accordingly,the size of each first opening OP1 may be relatively large in order toimprove transmittance of the sub-pixel SPX (refer to FIG. 1) or thedensity of the first openings OP1 may become high in order to improvethe resolution of the display panel 1000 (refer to FIG. 1).

The second mask MS2 includes a third edge ED3, a fourth edge ED4, and aplurality of second openings OP2. The second mask MS2 has a structureand a function that are substantially the as those of the first mask MS1except that the second mask MS2 includes the second openings OP2 insteadof the first openings OP1.

The third and fourth edges ED3 and ED4 are substantially parallel to thethird and fourth directions DR3 and DR4, respectively.

Pixel areas PA (e.g., pixel areas PA that correspond to the pixel areasPA of the display panel 1000 and the first mask MS1) are defined on thesecond mask MS2. The pixel areas PA are defined by the third and fourthedges ED3 and ED4. In more detail, the first-row and first-column pixelarea PA1_1 is spaced apart from a third corner CN3 formed by the thirdand fourth edges ED3 and ED4 by the third reference distance R3.

The second openings OP2 are formed to respectively correspond to thegreen areas GA of the pixel areas PA of the display panel 1000. Thesecond openings OP2 include third and fourth opening sides OS3 and OS4that are substantially parallel to the third and fourth directions DR3and DR4, respectively. Each of the second openings OP2 may have aquadrangular shape corresponding to the green area GA. The third andfourth opening sides OS3 and OS4 may be a short side and a long side ofthe second openings OP2, respectively.

The structure and function of the second openings OP2 are substantiallythe same as those of the first openings OP1 except that the secondopenings OP2 are disposed to correspond to the green areas GA of thepixel areas PA of the display panel 1000 instead of the red areas RA,and thus additional description thereof is omitted to avoid redundancy.

The third mask MS3 includes a fifth edge ED5, a sixth edge ED6, and aplurality of third openings OP3. The structure and function of the thirdmask MS3 are substantially the same as those of the first mask MS1except that the third mask MS3 includes third openings OP3 instead ofthe first openings OP1.

The fifth and sixth edges ED5 and ED6 are substantially parallel to thethird and fourth directions DR3 and DR4, respectively.

Pixel areas PA (e.g., pixel areas PA that correspond to the pixel areasPA of the display panel 1000, first mask MS1, and second mask MS2) maybe defined on the third mask MS3. The pixel areas PA are defined by thefifth and sixth edges ED5 and ED6. In more detail, the first-row andfirst-column pixel area PA1_1 is spaced apart from a fourth corner CN4formed by the fifth and sixth edges ED5 and ED6 by the third referencedistance R3.

The third openings OP3 are formed to respectively correspond to the blueareas BA of the pixel areas PA. The third openings OP3 include fifth andsixth opening sides OS5 and OS6 substantially parallel to the third andfourth directions DR3 and DR4. Each of the third openings OP3 may have aquadrangular shape corresponding to the blue area BA. The fifth andsixth opening sides OS5 and OS6 may be a short side and a long side ofthe third openings OP3, respectively.

The structure and function of the third openings OP3 are substantiallythe same as the structure and function of the first openings OP1 exceptthat the third openings OP3 are disposed to correspond to the blue areasBA of the pixel areas PA instead of the red areas RA, and thusadditional description thereof is omitted to avoid redundancy.

As an example, the second, fourth, and sixth opening sides OS2, OS4, andOS6 may have the same length, and the length of the first opening sideOS1 may be different from at least one of the third and fifth openingsOS3 and OS5.

FIG. 6 is a flowchart of a method of manufacturing a display panel usingthe mask set of FIG. 5, FIG. 7 is a plan view of a lower substrateaccording to the manufacturing method of FIG. 6, FIG. 8 is a plan viewof the lower substrate and a first mask for depositing a first colormaterial according to the manufacturing method of FIG. 6, FIG. 9 is aplan view of the lower substrate and a second mask for depositing asecond color material according to the manufacturing method of FIG. 6,FIG. 10 is a plan view of the lower substrate and a third mask fordepositing a third color material according to the manufacturing methodof FIG. 6, and FIG. 11 is a plan view of a display panel manufacturedaccording to the manufacturing method of FIG. 6.

Referring to FIGS. 6 and 7, the lower substrate 100 is provided (S1).The pixel areas PA1 to PA6 and the pixel definition lines PDL1 to PDL6are defined in the lower substrate 100.

Then, as shown in FIG. 8, the first color material is deposited on thelower substrate 100 using the first mask MS1 (S2). In more detail, thefirst mask MS1 is aligned on the lower substrate 100 to allow the firstopenings OP1 to overlap with the red areas RA defined on the lowersubstrate 100.

When the first mask MS1 is aligned, a shadow masking process is carriedout using the first mask MS1 to deposit the first color material on thelower substrate 100. In more detail, the first mask MS1 is interposedbetween the first color material and the lower substrate 100. The firstcolor material is heated to be evaporated. The evaporated first colormaterial moves to the lower substrate 100. Only a portion of theevaporated first color material is deposited on the red areas RA throughthe first openings OP1, and thus a red layer RL is formed in the redareas RA.

As an example, the first color material may be an organic light emittingmaterial that emits red light, but the present disclosure is not limitedthereto, and the red layer RL may be a red organic light emitting layerfor the red sub-pixel RPX (refer to FIG. 2), but the present disclosureis not limited thereto.

Referring to FIG. 9, the first mask MS1 is removed and the second colormaterial is deposited on the lower substrate 100 using the second maskMS2 (S3). As such, the second mask MS2 is aligned on the lower substrate100 to allow the second openings OP2 to overlap with the green areas GAdefined on the lower substrate 100.

When the second mask MS2 is aligned, a shadow masking process is carriedout using the second mask MS2 to deposit the second color material onthe lower substrate 100. In more detail, the second mask MS2 isinterposed between the second color material and the lower substrate100. The second color material is heated to be evaporated. Theevaporated second color material moves to the lower substrate 100. Onlya portion of the evaporated second color material is deposited on thegreen areas GA through the second openings OP2, and thus a green layerGL is formed in the green areas GA.

As an example, the second color material may be an organic lightemitting material that emits green light, but the present disclosure isnot limited thereto, and the green layer GL may be a green organic lightemitting layer for the green sub-pixel GPX (refer to FIG. 2), but thepresent disclosure is not limited thereto.

Referring to FIG. 10, the second mask MS2 is removed and the third colormaterial is deposited on the lower substrate 100 using the third maskMS3 (S4). As such, the third mask MS3 is aligned on the lower substrate100 to allow the third openings OP3 to overlap with the blue areas BAdefined on the lower substrate 100.

When the third mask MS3 is aligned, a shadow masking process is carriedout using the third mask MS3 to deposit the third color material on thelower substrate 100. In more detail, the third mask MS3 is interposedbetween the third color material and the lower substrate 100. The thirdcolor material is heated to be evaporated. The evaporated third colormaterial moves to the lower substrate 100. Only a portion of theevaporated third color material is deposited on the blue areas BAthrough the third openings OP3, and thus a blue layer BL is formed inthe blue areas BA.

As an example, the third color material may be an organic light emittingmaterial that emits blue light, but the present invention is not limitedthereto, and the blue layer BL may be a blue organic light emittinglayer for the blue sub-pixel BPX (refer to FIG. 2), but the presentinvention is not limited thereto.

Referring to FIG. 11, the red layer RL, the green layer GL, and the bluelayer BL of the red, green, and blue sub-pixels RPX, GPX, and BPX areformed to respectively correspond to the red, green, and blue areas RA,GA, and BA of each of the pixel areas PA.

As described above, because the first to third masks MS1 to MS3 (referto FIG. 5) have high strength, the density of the first to thirdopenings OP1 to OP3 of the first to third masks MS1 to MS3 is high.Accordingly, when the deposition process is performed by using the firstto third masks MS1 to MS3, the number of the pixels PX (refer to FIG. 1)may be increased.

While certain embodiments of the present invention have been illustratedand described, it is understood by those of ordinary skill in the artthat certain modifications and changes can be made to the describedembodiments without departing from the spirit and scope of the presentinvention as defined by the following claims, and equivalents thereof.

What is claimed is:
 1. A deposition mask set comprising: a first mask; asecond mask; and a third mask, wherein the first mask comprises: a firstedge parallel to a first direction; a second edge parallel to a seconddirection; and a plurality of quadrangular first openings, each of thefirst openings comprising a first opening side that is parallel to athird direction and a second opening side that is parallel to a fourthdirection, each of the first openings corresponding to a first colorarea at one pixel area of pixel areas, wherein the quadrangular firstopenings are in a matrix form along the first and second directions, andthe quadrangular first openings are adjacent each other in the first andsecond directions, wherein the third and fourth directions are notparallel to the first and second directions, wherein the second maskcomprises: a third edge parallel to the first direction; a fourth edgeparallel to the second direction; and a plurality of second openings ina matrix form along the first and second directions, each of the secondopenings comprising a third opening side that is parallel to the thirddirection and a fourth opening side that is parallel to the fourthdirection, each of the second openings corresponding to a second colorarea at the one pixel area, wherein the second color area is adjacent tothe first color area in the third direction, wherein the third maskcomprises: a fifth edge parallel to the first direction; a sixth edgeparallel to the second direction; and a plurality of third openings in amatrix form along the first and second directions, each of the thirdopenings comprising a fifth opening side that is parallel to the thirddirection and a sixth opening side that is parallel to the fourthdirection, each of the third openings corresponding to a third colorarea at each of the one pixel area, wherein the third color area isadjacent to the first and second color areas in the third directionwithin the one pixel area, and wherein the first to third color areasare not alternately arranged in the first and second directions.
 2. Thedeposition mask set of claim 1, wherein the first mask comprises a firstsection, a number of the first openings arranged along a first line thatis parallel to the third direction in the first section from among thefirst openings being less than a number of the first openings arrangedalong a second line that is parallel to the third direction in the firstsection from among the first openings, wherein the first openingsarranged along the first line overlap a first pixel definition line, thefirst openings arranged along the second line overlap a second pixeldefinition line, the first and second pixel definition lines beingparallel to the third direction and overlapping with the first section,and wherein the second pixel definition line is adjacent to the firstpixel definition line in the fourth direction.
 3. The deposition maskset of claim 2, further comprising a second section adjacent to thefirst section in the fourth direction, a number of the first openingsarranged along a third line parallel to the third direction in thesecond section from among the first openings being equal to a number ofthe first openings arranged along a fourth line parallel to the thirddirection in the second section from among the first openings, whereinthe first openings arranged along the third line overlap a third pixeldefinition line, the first openings arranged along the fourth lineoverlap a fourth pixel definition line, the third and fourth pixeldefinition lines being parallel to the third direction and overlappingwith the second section, and wherein the fourth pixel definition line isadjacent to the third pixel definition line in the fourth direction. 4.A deposition mask set comprising: a first mask, the first maskcomprising: a first edge parallel to a first direction; a second edgeparallel to a second direction; and a plurality of quadrangular firstopenings, each of the first openings comprising a first opening sidethat is parallel to a third direction and a second opening side that isparallel to a fourth direction, each of the first openings correspondingto a first color area at the one pixel area, the quadrangular firstopenings being in a matrix form along the first and second directions,the quadrangular first openings being adjacent each other in the firstand second directions, the third and fourth directions being notparallel to the first and second directions; a first section, a numberof the first openings arranged along a first line that is parallel tothe third direction in the first section from among the first openingsbeing less than a number of the first openings arranged along a secondline that is parallel to the third direction in the first section fromamong the first openings; a second section adjacent to the first sectionin the fourth direction, a number of the first openings arranged along athird line parallel to the third direction in the second section fromamong the first openings being equal to a number of the first openingsarranged along a fourth line parallel to the third direction in thesecond section from among the first openings; and a third sectionadjacent to the second section in the fourth direction, a number of thefirst openings arranged along a fifth line that is parallel to the thirddirection in the third section from among the first openings beinggreater than a number of the first openings arranged along a sixth linethat is parallel to the third direction in the third section from amongthe first openings, wherein the first openings arranged along the firstline overlap a first pixel definition line, the first openings arrangedalong the second line overlap a second pixel definition line, the firstand second pixel definition lines being parallel to the third directionand overlapping with the first section, wherein the second pixeldefinition line is adjacent to the first pixel definition line in thefourth direction, wherein the first openings arranged along the thirdline overlap a third pixel definition line, the first openings arrangedalong the fourth line overlap a fourth pixel definition line, the thirdand fourth pixel definition lines being parallel to the third directionand overlapping with the second section, wherein the fourth pixeldefinition line is adjacent to the third pixel definition line in thefourth direction, wherein the first openings arranged along the fifthline overlap a fifth pixel definition line, the first openings arrangedalong the sixth line overlap a sixth pixel definition line, the fifthand sixth pixel definition lines being parallel to the third directionand overlapping with the third section, and wherein the sixth pixeldefinition line is adjacent to the fifth pixel definition line in thefourth direction.
 5. The deposition mask set of claim 1, wherein thefirst and second directions are perpendicular to each other, and whereinthe third and fourth directions are perpendicular to each other.
 6. Thedeposition mask set of claim 5, wherein the first and third directionsform an angle of about 45 degrees.
 7. The deposition mask set of claim1, wherein the first, second, and third color areas of the one pixelarea are not overlapped with each other.
 8. The deposition mask set ofclaim 7, wherein centers of the first, second, and third color areas ofthe one pixel area are aligned in the third direction.
 9. The depositionmask set of claim 8, wherein a length of the first opening side isdifferent from a length of at least one of the third and fifth openingsides.
 10. The deposition mask set of claim 8, wherein a length of thesecond, fourth, and sixth opening sides is the same.
 11. The depositionmask set of claim 1, wherein the third color area at the one pixel areais nearer to the first color area at an adjacent one of the pixel areasthan to the second color area at the one pixel area.